Dishwasher with downwardly movable door counterbalanced by spring-biased toggle joints

Abstract

A dishwasher having a tank containing wash water disposed below a dishwashing compartment and means for removing water from the tank and forcing it through upper and lower revolving spray arms for washing the dishes, the wash water being returned to the tank by gravity. A hood overlies the top of the wash and rinse compartment and a door for closing the compartment is movable downwardly into the tank for opening the compartment, the weight of the door being yieldingly held in closed or open position by spring biased toggle joints that are positioned in the tank. A U-shaped member is removably secured to the hood that overlies the dishwashing compartment and this member acts as a door stop when the door is in its raised and closed position. A removal of the member from the hood permits the door to be removed from the dishwasher.

I claim: 
     
       1. A dishwashing machine comprising: a. a tank for holding water for washing dishes;   b. a dish basket receiving compartment disposed above said tank;   c. a hood covering the top area of the compartment and supported by a back that also forms a wall of said tank;   d. a door movable vertically from a top position where it cooperates with said back and said hood for closing the compartment, to a bottom position where it is received in said tank and permits access into and out of the compartment;   e. spring biasd toggles connected to said door and said tank for counterbalancing said door for supporting it at all elevations from closed to open position, said spring biased toggles including a pair of toggles arranged at opposite sides of said tank, each toggle comprising a lower toggle arm having one end pivotally mounted at the bottom of said tank and adjacent to the vertically movable door, an upper toggle arm having one end attached to the pivotal connection between the two arms and its other end connected to an anchor collar that has means for adjusting its vertical and horizontal position for altering the tension and angle said spring makes relative to the pivotal connection between the two toggle arms;   f. said means for adjusting the vertical and horizontal position of said anchor collars includes an upright mounted in said tank for each anchor collar;   g. a sleeve adjustable vertically on each upright;   h. a threaded rod extending radially from each sleeve and supported thereby;   i. a tubular member for each threaded rod and having a threaded connection therewith;   j. a cross piece interconnecting the two tubular members and supporting said anchor collars; and   k. whereby said anchor collars can be moved into the correct position both vertically and horizontally by adjusting said sleeves on said uprights and adjusting said threaded rods for moving said tubular members so as to apply the proper tension and angle on said springs to substantially counterbalance the weight of said door.   
     
     
       2. The combination as set forth in claim 1: and in which a. said doors being three sided and having a pair of guide rollers at each side thereof and adjacent to the open rear thereof;   b. said back supporting vertical guide channels, one for each pair of door guiding rollers, said rollers moving freely in said channels during any vertical movement of said door;   c. said hood having its front and two parallel sides spacd inwardly a distance just sufficient to permit the top of the door to clear the hood in its upward movement when it is desired to remove said door from said dishwasher, the guide rollers being disconnected from said door for this purpose;   d. a U-shaped member having a front designed to abut the front of said hood when the member is secured to said hood and having spaced parallel sides designed to abut the two sides of said hood for enlarging the overall area of said hood, the underside of said U-shaped member lying below the underside of said hood and lying in the path of the vertically movable door; and   e. whereby an upward movement of the door into closed position will cause the top of the door to contact the underside of said U-shaped member for closing the compartment.   
     
     
       3. The combination as set forth in claim 1, and in which a. each toggle having its two arms making an acute angle with respect to each other when said cover is in its lowermost and open positon, the adjustable anchoring means for said spring being positioned so that the length of each spring substantially bisects the acute angle formed by the adjacent pair of toggle arms, the anchoring means causing the springs to exert a pull at the pivotal connection between the two arms of each pair of toggles for swinging the arms from an acute angle to a obtuse angle as they move the door from a bottom "open" position to a top "closed" position, the springs being stretched to a greater extent and exerting a greater pulling force and at the proper angle on the pivotal connection between the arms of each pair when they make an acute angle with respect to each other than when they make an obtuse angle.